1. Field of the Invention
The present invention relates to a process for preparing poly(phenylene oxide) asymmetric gas separation membranes by forming a solution of the polymer in an aprotic solvent or mixtures of aprotic solvents or mixtures of one or more aprotic solvents with another solvent or non-solvent forming a premembrane followed by evaporation of solvent and coagulation.
2. Prior Art
U.S. Pat. No. 3,350,844 discloses the use of dense poly(phenylene oxide) membranes for gas separations.
U.S. Pat. No. 3,709,774, U.S. Pat. No. 3,762,136, and U.S. Pat. No. 3,852,388 disclose asymmetric poly(phenylene oxide) gas separation membranes and a process to prepare same.
EPO-216,633 discloses composite gas separation membranes comprising a plasma condensate on top of a porous poly(phenylene oxide) support membrane. The gas selectivity observed is attributed to the plasma condensate layer.